[NFC] [X86] Fix scan-build complaining
[NFC] [X86] Fix scan-build complaining

Summary:
Remove unused variable. This fixes bug:
https://bugs.llvm.org/show_bug.cgi?id=42526

Signed-off-by: pengfei <pengfei.wang@intel.com>

Reviewers: RKSimon, xiangzhangllvm, craig.topper

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64389

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@365473 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang